Fix misc jar remapping issues.

src/main/java/net/fabricmc/loom/task/PrepareJarRemapTask.java

@@ -79,14 +79,12 @@ public abstract class PrepareJarRemapTask extends AbstractLoomTask {
 
 		workQueue.submit(ReadInputsAction.class, params -> {
 			params.getTinyRemapperBuildServiceUuid().set(UnsafeWorkQueueHelper.create(getProject(), remapJarTask.getTinyRemapperService()));
-			params.getInputTagName().set(remapJarTask.getInputTagName());
 			params.getInputFile().set(getInputFile());
 		});
 	}
 
 	public interface ReadInputsParams extends WorkParameters {
 		Property<String> getTinyRemapperBuildServiceUuid();
-		Property<String> getInputTagName();
 		RegularFileProperty getInputFile();
 	}
 
@@ -102,7 +100,7 @@ public abstract class PrepareJarRemapTask extends AbstractLoomTask {
 			final TinyRemapper tinyRemapper = tinyRemapperService.getTinyRemapperForInputs();
 			final Path inputFile = getParameters().getInputFile().getAsFile().get().toPath();
 
-			tinyRemapper.readInputsAsync(tinyRemapperService.createTag(getParameters().getInputTagName().get()), inputFile);
+			tinyRemapper.readInputsAsync(tinyRemapperService.getOrCreateTag(inputFile), inputFile);
 		}
 	}
 }

src/main/java/net/fabricmc/loom/task/RemapJarTask.java

@@ -126,7 +126,6 @@ public abstract class RemapJarTask extends AbstractRemapJarTask {
 			params.getJarManifestService().set(JarManifestService.get(getProject()));
 			params.getTinyRemapperBuildServiceUuid().set(UnsafeWorkQueueHelper.create(getProject(), tinyRemapperService.get()));
 			params.getRemapClasspath().from(getClasspath());
-			params.getInputTagName().set(getInputTagName());
 
 			final boolean legacyMixin = extension.getMixin().getUseLegacyMixinAp().get();
 			params.getUseMixinExtension().set(!legacyMixin);
@@ -193,7 +192,6 @@ public abstract class RemapJarTask extends AbstractRemapJarTask {
 	public interface RemapParams extends AbstractRemapParams {
 		ConfigurableFileCollection getNestedJars();
 		ConfigurableFileCollection getRemapClasspath();
-		Property<String> getInputTagName();
 
 		Property<Boolean> getUseMixinExtension();
 
@@ -243,7 +241,7 @@ public abstract class RemapJarTask extends AbstractRemapJarTask {
 		private void remap() throws IOException {
 			try (OutputConsumerPath outputConsumer = new OutputConsumerPath.Builder(outputFile).build()) {
 				outputConsumer.addNonClassFiles(inputFile);
-				tinyRemapper.apply(outputConsumer, tinyRemapperService.getTag(getParameters().getInputTagName().get()));
+				tinyRemapper.apply(outputConsumer, tinyRemapperService.getOrCreateTag(inputFile));
 			}
 		}
 
@@ -323,9 +321,4 @@ public abstract class RemapJarTask extends AbstractRemapJarTask {
 	public TinyRemapperService getTinyRemapperService() {
 		return tinyRemapperService.get();
 	}
-
-	@Internal
-	String getInputTagName() {
-		return getProject().getPath() + getName();
-	}
 }

src/main/java/net/fabricmc/loom/task/service/JarManifestService.java

@@ -53,7 +53,7 @@ public abstract class JarManifestService implements BuildService<JarManifestServ
 		Property<MixinVersion> getMixinVersion();
 	}
 
-	public static Provider<JarManifestService> get(Project project) {
+	public static synchronized Provider<JarManifestService> get(Project project) {
 		return project.getGradle().getSharedServices().registerIfAbsent("LoomJarManifestService:" + project.getName(), JarManifestService.class, spec -> {
 			spec.parameters(params -> {
 				LoomGradleExtension extension = LoomGradleExtension.get(project);

src/main/java/net/fabricmc/loom/task/service/MixinMappingsService.java

@@ -52,7 +52,7 @@ public final class MixinMappingsService implements SharedService {
 		return mixinMapping;
 	}
 
-	static MixinMappingsService getService(SharedServiceManager sharedServiceManager) {
+	static synchronized MixinMappingsService getService(SharedServiceManager sharedServiceManager) {
 		return sharedServiceManager.getOrCreateService("MixinMappings", () -> new MixinMappingsService(sharedServiceManager));
 	}
 

src/main/java/net/fabricmc/loom/task/service/SourceRemapperService.java

@@ -109,9 +109,7 @@ public final class SourceRemapperService implements SharedService {
 
 	private synchronized void doRemap(Path srcPath, Path dstPath, Path source) {
 		try {
-			synchronized (mercury) {
 			mercury.get().rewrite(srcPath, dstPath);
-			}
 		} catch (Exception e) {
 			LOGGER.warn("Could not remap " + source + " fully!", e);
 		}

src/main/java/net/fabricmc/loom/task/service/TinyRemapperService.java

@@ -28,11 +28,11 @@ import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.concurrent.ConcurrentHashMap;
 
 import org.gradle.api.Project;
 
@@ -73,7 +73,7 @@ public class TinyRemapperService implements SharedService {
 	}
 
 	private TinyRemapper tinyRemapper;
-	private final Map<String, InputTag> inputTagMap = new ConcurrentHashMap<>();
+	private final Map<String, InputTag> inputTagMap = new HashMap<>();
 	private final HashSet<Path> classpath = new HashSet<>();
 	// Set to true once remapping has started, once set no inputs can be read.
 	private boolean isRemapping = false;
@@ -92,16 +92,15 @@ public class TinyRemapperService implements SharedService {
 		tinyRemapper = builder.build();
 	}
 
-	public InputTag createTag(String key) {
-		if (inputTagMap.containsKey(key)) {
-			throw new IllegalStateException("Input tag already exists for key: " + key);
+	public synchronized InputTag getOrCreateTag(Path file) {
+		InputTag tag = inputTagMap.get(file.toAbsolutePath().toString());
+
+		if (tag == null) {
+			tag = tinyRemapper.createInputTag();
+			inputTagMap.put(file.toAbsolutePath().toString(), tag);
 		}
 
-		return inputTagMap.put(key, tinyRemapper.createInputTag());
-	}
-
-	public InputTag getTag(String key) {
-		return Objects.requireNonNull(inputTagMap.get(key), "Input tag not found for: " + key);
+		return tag;
 	}
 
 	public TinyRemapper getTinyRemapperForRemapping() {